1. Field of the Invention
The invention relates to saw blade sharpening devices and is directed more particularly to apparatus for sharpening combination saw blades.
2. Description of the Prior Art
Automatic machines for sharpening saw blades are well known in the art. The machines include a rotary grinding head which is reciprocally moveable into and out of engagement with regularly spaced cutting teeth on the blade. The blade is conventionally mounted on a spindle which permits rotation of the blade incrementally, to bring the cutting teeth into position for engagement with the grinding head.
Blades generally referred to as "combination" blades, include a series of cutting teeth, usually followed by a "raker" tooth, which is essentially a cleaning tooth and is generally preceded by a "gullet" or deep depression into which cuttings may fall and be retained briefly before falling from the blade. The raker tooth is shaped differently from the cutting teeth and, of course, the gullet is shaped entirely differently from either the cutting teeth or raker teeth. Because of the interrupted configuration of the periphery of the combination blade, the ordinary automatic machines are not adapted to sharpen such blades and it is customary to sharpen the blades by hand, a procedure which usually reduces the geometrical precision of the blade.
There is a need for apparatus which may be used in combination with a regular automatic sharpening machine and adapt the machine to the automatic sharpening of combination blades.